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} r`i 19 April 2006 AGE-NC Project No. 98-0534 Page 2 of 3 is in an area of known MTBE impact at shallower depths, and therefore must be destroyed by over-drilling according to the Standards. For non-impacted wells (possible MW-1), the exposed 2-inch diameter well casing will be completely backfilled with a Portland type 11 cement grout mixture. In accordance with Section 13.12.10., the cement grout mixture will be applied under pressure (25 psi for at least 10-minutes) to ensure grout penetration into the filter pack. The grout mixture will consist of a nominal six gallons of water to 94-pound sack portland cement ratio. In accordance with Section 13.12.12. and in preparation for well destruction,over-drilling of the well casing will be performed to a minimum depth of approximately 3 feet bsg utilizing 20-inch hollow stem augers or equivalent.A six inch riser of casing will be exposed for sealing purposes.Following backfilling procedures,the remaining void space(inside the annular space left by over-drilling activities) will be completely backfilled with a neat cement to surface grade. For impacted wells, and those in an area of known or suspected contamination (MW-2 thorough MW-9), Section 13.17.6. of the Standards will be followed for destruction procedures. Wells will be drilled-out to their total depth utilizing 8-inch diameter hollow-stem augers. All original well construction materials will be removed(including well casing,screen,filter pack,and annular seal) to ensure that no residual contamination is sealed within the abandoned borehole. The remaining borehole will then be backfilled to surface grade with neat cement. Soil cuttings generated during over-drilling activities and rinseate will be containerized in properly labeled Department of Transportation(D.O.T.)-approved 55-gallon drums, and stored on-site in an area lacking public access. AGE will submit a well destruction permit application as required by the EHD Ietter. I f Advanced GeOCnvirnnmPnf.1 i..,.